Riverhead, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 36.5 °F (low) to 47.6 °F (high). Annual precipitation averages 47 Inches. Riverhead is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -21.1 °F | -17.7 °F | 2184.4 in. |
| February | -21.6 °F | -18.3 °F | 2209.8 in. |
| March | -20.7 °F | -17.7 °F | 2057.4 in. |
| April | -18.6 °F | -15.3 °F | 2489.2 in. |
| May | -16.3 °F | -12.5 °F | 2286 in. |
| June | -14.1 °F | -10 °F | 2108.2 in. |
| July | -11.3 °F | -7.3 °F | 2362.2 in. |
| August | -10.6 °F | -6.7 °F | 2159 in. |
| September | -12.3 °F | -8.5 °F | 2717.8 in. |
| October | -14.4 °F | -11.4 °F | 3352.8 in. |
| November | -16.7 °F | -13.8 °F | 3378.2 in. |
| December | -19.1 °F | -16.3 °F | 3022.6 in. |
| Annual | 36.5 °F | 47.6 °F | 47.03 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |